RESUMO
The effect of intraperitoneal injection of dimethyl sulfoxide (DMSO) in a dose of 175 mg/kg on the catalase activity of the myocardium of adult and old-aged rats subjected to immobilization stress was studied. DMSO injection promoted catalase activation in the heart of old-aged rats subjected to immobilization and practically had no effect on the analogous parameter in adult animals. Together with activation of the enzyme, changes occur in it which raise the effectiveness of the catalase response under conditions of stimulated production of active forms of oxygen in oxidation stress (increased affinity for the substrate, more expressed changes in activity in response to a change in pH of the medium, limited effect of the inhibitors on the enzyme).
